Re: [DNSOP] SVCB without A/AAAA records at the service name

Martin Thomson <mt@lowentropy.net> Sun, 17 January 2021 22:57 UTC

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Date: Mon, 18 Jan 2021 09:56:42 +1100
From: "Martin Thomson" <mt@lowentropy.net>
To: dnsop@ietf.org
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Subject: Re: [DNSOP] SVCB without A/AAAA records at the service name
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On Sat, Jan 16, 2021, at 06:01, Ben Schwartz wrote:
> FWIW, I think this is really an editorial question.  
...
> https://github.com/MikeBishop/dns-alt-svc/pull/288
... 
> https://github.com/MikeBishop/dns-alt-svc/pull/289

Neither of these work for me.  Both do the same thing in different ways.  Both are unspecific about what changes might be made to the algorithm.  That leads to far less certainty about how the information is consumed than I think is sensible.

What I'm looking for here is for the specification to describe what happens when the protocol needs to fall back to A/AAAA and what happens when it does not.  The first is important, because that is what HTTP will need.  The second because I think that is a better approach for any new protocol (I had hoped that webtransport would be able to take advantage of this, but they made a different choice for reasons I'm yet to understand).